The present invention relates to liquid crystalline polyesters resulting from the intercondensation of bis(4-hydroxyphenyl)ether, 4,4'-dihydroxypolyorganosubstituted biphenyl, and hydroxybenzoic acid which are further intercondensed with terephthalic acid, or isophthalic acid or mixtures of terephthalic acid and isophthalic acid. More particularly, the present invention relates to liquid crystalline polyester compositions exhibiting improved processing and melt flow characteristics.
Prior to the present invention, some commercially available liquid crystalline polyester compositions consisted of intercondensed hydroxybenzoic acid, 4,4'-biphenol, and terephthalic acid. Although these polyesters exhibit high heat resistance, they require a temperature of above 400.degree. C. to process. Another commercially available liquid crystalline polyester composition having improved processing capabilities consists of intercondensed hydroxynaphthoic acid, and hydroxybenzoic acid. It would be desirable, therefore, to provide additional liquid crystalline polyesters with improved processing characteristics and oxidative stability as well as valuable physical characteristics in both the filled and unfilled state.